With the increasingly extensive use of the mail, the mail exerts a growing important effect in the work and the life of people. However, more and more mails, such as junk mails or advertisement mails bring processing burden for people.
Therefore, a Sieve mail filtering language is developed, and specific operations may be performed on a mail meeting specific conditions of a user by using the language, such as, deleting the mail, moving the mail to a specific mailbox, or forwarding the mail to another address. The operations may be implemented through a mail client or a mail server. Such mechanism reduces the mail processing burden for the user, and when the mail receiver cannot respond to the received mail in time, the mails meeting the specific conditions are automatically replied.